Automatic circuit-controlling device.



J. H. KIEFER.

AUTOMATIC CIRCUIT CONTROLLING DEVICE.

APPLICATION FILED AUG. 24| '|91 l.

Pafented June 19, 1917.

InYEnJI' WIIESSEYS 'miran srarss raanna oratori.'

JAMES H. KIEFER, 0F DAYTON, OHIO, ASSIGNOR T0 THE DAYTON ENGINEERINGLABORATORIES C0., A CORPORATION 0F OHIO.

AUTOMATIC CIRCUIT-CONTROLLING DEVICE.

Specification of Letters Patent.

liatented June 19, 1917.

Application led August 24, 1911. Serial No. 645,887.

To all 'whom it may concern.'

Be it known that I, JAMEs H. KIEFER, a citizen of the United States,residing at Dayton, county of Montgomery, and State of Ohio, haveinvented certain new and useful Improvements in AutomaticCircuit-Controlling Devices, of which the following is a full, clear,and exact description.

This invention relates to improvements in circuit controlling devices,more particularly for automatically breaking an electric circuit undercertain conditions, and automatically restablishing the same.

The devices shown herein are illustrated and described more particularlywith reference to electricA ignition systems, and it is one of theobjects of the present invention to provide an automatic circuitcontrollin device which will be an advantage in ignition systems, in theway of increasing the etliciency of said systems and preventing mis-Aoperation or injury thereto.

But, it is to be understood that. these improvements are not limited toignition devices, but are applicable to other forms of electricalsystems, wherein such automatic controlling features are advantageous.

As one of the objects of the present invention, in so far as applied toan ignition system, the aim is to prevent an excessive amount of currentfrom passing through the main circuit of the ignition system, by pro-`viding an automatic circuit breaker which operates 'tobreak the maincircuit or cut down the flow of current therethrough, whenever the maincurrent rises beyond a certain predetermined point. Or, in anotheraspect, the object is to operate the circuit breaker automatically,after a certain time interval of How of the current.k

And at the sametime it is one of the purposes of the invention toprovide for the reestablishment of the circuit through the circuitbreaker automatically, according to the condition of theapparatus inthemain circuit.

Further objects and advantages incidental to the present invention willbe apparent from the following description, reference being had to theaccompanying drawing,l

wherein a preferred form of embodiment of the invention is illustrated.l A

Figure l is a partly diagrammatic View of the electrical circuits andconnections embodied in the present invention, the armature of thecontrolling mechanism being shown in attracted' position and the maincircuit of said system being broken.

Fig. 2 is a detail view, partly in section, of the controlling orregulating element, the armature in the present view being shown innormal position.

It may be stated that in the particular form shown herein, the desire isto provide against deterioration of batteries supplying an electriccurrent for the ignition circuit, wherein 1t some times occurs that thetiming mechanism may come to rest at suoli a point that it leaves thecontacts permanently closed. This would result in a continuous iiow ofthe battery current, and a running down of the battery, and otherdisadvantages might also follow.

But, with the application of the present improvements, the system isprovided with a circuit breaker which automatically breaks the mainignition circuit, in case the timer contacts should happen to come torest at such a position. And then the apparatus is further arranged sothat the circuit breaker remains locked in circuit breaking position.and stays this way until the timing mechanism of the main circuit isagain set in motion, so as to break thc main circuit. whereupon thecircuit breaker is automatically released or actuated, so as toreestablish through it the main circuit connection and thus leave thesystem ready for operation by a continued movement of the timingmechanism.

Thus, in the particular mode of use, the automatic circuit breakeroperates only under those abnormal or unusual conditions, wherein thetimer has stopped on Contact; but then the circuit breaker isautomatically closed again as soon as the timer resumes its normaloperation of breaking and making the circuit at that' point.

It will be obvious from the description which follows hereinafter` thatthe same protective feature resides in this automatic circuit breaker,in case the main circuit is closed or grounded by any other mea-ns thanthe timer, so as therefore to prevent undue running down of thebatteries.

It is furthermore one of the features of the present improvements thatin bringing about the operation of this circuit breaker, use is made ofan iron wire. The. characteristics of such an iron wire are that uponpassage of abnormal amount of current therep through, or for a prolongedtime, the iron Wire increases in resistance; this being some timesexpressed as having a positive coefficient of resistance.

Now, it will be seen that if this iron Wire is utilized as partl of theapparatus to operate the circuit breaker, by its heating e'ect, itfollows that an increase of `resistance thereof will at the same timeserve the additional purpose of cutting down the flow of main current,so as to lessen any deleterious effects of the breaking of that current.

In Fig. 1, there is disclosed an ignition system, wherein a controllingor regulating mechanism is lso arranged that upon a flow of current,over and above a predetermined amount, said regulating mechanism willlead Wires 34 and 35.

tend to automatically, irst, effect the reduction in the flow of currentthrough the main circuit and secondly, upon a continuation of this flowof current, will positively effect the opening or breaking of thecircuit, whereby the flow of current will be completely eut off, thiscondition being maintained until the mechanism is again placed in normaloperating position.

In Fig. 1, the, numeral 20 designates a supply or source of electricalenergy, such as a storage battery or accumulator of approved type. Onepole of this accumulator or battery is connected with the primaryWinding 22 oftheN induction coil, by means ofthe wire 21, while theopposite end of said primary winding is connected to the stationarycontact 24 of the timing mechanism 25, by means of the lead wire 23.This stationary Contact member of the timer is intermittently engaged orplaced in contact with the movable contact plate 27, which in turn isactuated by means of the cam 28, driven through any suitable mechanismactuated lby the engine.

It will, of course, be understood that it is not intended to limit thepresent invention to a system embodying a timer mechanism of the typeherewith shown and described, but rather that any approved timer may beemployed. The timer herewith shown and described, is substantially thesame as that which forms the subject matter of the copending applicationof Charles F. Kettering, filed Dee. 15, 1911. Serial No. 592,291.

The timer cam 28 is electrically connected by means of the Wire 29, withthe variable resistance coil or winding 30, which surrounds a novellyconstructed contactplate 31, of the controlling mechanism.

One end ofthe variable resistance coil 30,v

is secured directly to the contact plate 31, which in turn is normallyin contact with the plate 33, said plate 33 being electricallyconnected. to the battery 20, by means From .the above, it will beObvious 'that the of,4 the ath of current under`normal conditions, willbe as follows z-From the battery, the current will flow through the wire21, primary Winding 22 of the induction coil, W1re 23, through thecontact members 24 and 27,

and timer cam 28, into wire 29, by which it is Y. conveyed to thevariable resistance coil 30,

contact plate 31, eoperating contact plate 33, into Wire 34 and back tothe battery via wire 35, it being understood that the contact plates 31and 33 are normally closed as is shown in Fig. 2. i

So long as conditions remain normal, the above described path of thecurrent will be unchanged, but upon event of the accidental continuedclosing of the main circuit, either because the contacts of the timingmechanism are left in closed position, when the engine is stopped or ininoperative position or from any other reason; the variable resistancecoil 30, which is constructed of iron wire, will immediately tend toheat up, because of the continuous passage of an excessive amount o'fcurrent therethrough. It is a well known property of iron Wire, that asits temperature or heat increases, the resistcv ance thereof increasesin a like degree; and it will therefore be obvious that the supply ofcurrent passing through the main circuit will bereduced as theresistance thereof increases.

The means of controlling the passage of current'through the main circuitof the ignition system, by interposing an iron wire resistance therein,which as has heretofore been explained, possesses the property ofincreasing its resistance as its temperature increases, forms one of themain features of the co-pending application of Charles F. Kettering, ledAug. 11, 1911, Serial No. 643,547, which in turn is a divisionalapplicationV of the co-pending application of Charles F. Kettering, ledApril 17, 1911, Serial No. 621,512.

As an improvement upon the devices shown in the applications justreferred to, and with advantages which will be apparent to those skilledin the art, the present invention embodies means controlled by thevaribleiron wire resistance, which will automatically effect thepositive breaking or opening l of themain circuit when the iron wire hasbecome heated to a predetermined degree.

This means comprises the contact plate 31, constructed of any metalwhich has a high coefficient of expansion, such for instance, as

is thought will be obvious from an plates which are clearly shown inFigi 2, are soldered together, throughout their entire length and arevwrapped or Wound with any suitable insulating material, as is shown at18. The iron wire coil 30 is located outside of this insulation, one endof said iron Wire resistance being connected to the contact plate 31 ortothe plate having a relatively high coeiicient of expansion, as at 19.The contact plate 31 is extended beyond the plate 32 as is shown inFigs. 1 and 2; the extreme outer end thereof, resting directly inalinement with one end of the pivoted armature 36, said armature havingan insulated button 37, which is adapted `to rest against the plate 31and to maintain the same in the position shown in Fig. 1, when thearmature :is-attracted by the energization of the core 47. Thestationary plate 33 and the compound plate 31 are mounted in anysuitable insulating block 40. In order to maintain the contact plates 31and 33 in normally closed position, the spring 41 is so mounted that oneend thereof, impinges the plate 31, directly over the point where thepivoted. armature engages the under side thereof.

The pivoted armature above referred to, is mounted on an-L-shaped frame45, which supports the electro-magnet 4G. This electro-magnet comprisesa central core 47, rigidly secured at one end, to the frame 45 and isprovided with a pole ypiece 49 at the opposite end and so positioned,that when the said core is energized, the pivoted armature will beattracted by and drawn toward the said pole piece.

The magnet core 47 is provided with a Winding of Wire of relatively highresistance, as at 50, the opposite ends of which are connectedrespectively with the wires 52 and 53, the wire 52 connecting with thewire 29, which as has heretofore been described, connects with the ironwire resistance 30 and the cam 28 of the timer mechanism, while the wire53 is joined with the wire 35 which leads directly to the battery.

The arrangement of the secondary circuits togetherwith vthe secondaryWinding of the induction coil which is yshown at 55, may be of the usualdesign, and inasmuch as they do not enter into the novel features of thepresent invention, no further description thereof will be given. f

The operation of the entire controlling system will be as follows Theordinary circuit of the current Vunder normal conditions, has heretoforebeen described, and it inspection of Fig.- 1. However, when the timercontacts are brought to rest in the position shown in Fig.'1, thusclosing the main circuit, it will he seen that the continuous flow ofcurrent will initially occur through the main circuit gf the ignitionsystem. This continuous ow of current will necessarily pass through theresistance winding 30, which as has heretofore been stated, comprises aniron wire, or other variable resistance member, having substantially thesame properties that the iron wire possesses, that is, the property ofincreasing its resistance as its temperature increases. This winding,however, when in its normal condition, is of much -lower resistance thanthe fine wire winding 50.`

Now upon a continuation of this iow of current, the temperature of theiron wire will gradually increase and with the corresponding increase inits resistance, will tend to cut down the How of current through themain circuit, to practically a negligible quantity. The heat generatedor given off from the iron wire, when in this condition, will beintroduced into the contact plate 31 and in a slight degree into thereinforcing plate 32, carried by the plate 31. -As has been explainedheretofore, the plate 31 is composed of metal having a relatively highcoecient of' expansion, as compared with the coefficient of expansion ofthe metal forming the reinforcing plate 32 and as the heat increases insaid plates, the tendency of the plate 31 to expand, will be retarded ina certain degree by the difference in the coefiicient of expansion ofthe reinforcing plate 32 and the plate 31, which will result in thebowing or warping of the plate 31, away from the contact plate 33, thuscompletely breaking the main circuit by opening contacts 31 and 33. f

If some supplemental means were not provided tov maintain the circuit inthis broken or open condition, the contacts would immediately close, aslsoon as the plates 31'and 32 became suiciently cool to retract them fromtheir expanded position. In order tomaintain the circuit in opencondition, throughout the time interval that the timer contacts remainin continued closed position, the wire 29 which connects with theresistance coil 30, is also connected at the point 56 with the wire52,which joins with one terminal of the fine wire coil, or high resistancewinding 50, while the opposite end thereof connects through the mediumof the wire 53, with the direct battery connection 35.

Supposing that the timer contacts are in closed position, as shown inFig. 1, the current will first pass through the-wire 21,A

primary winding 22, wire 23, contacts 24 and 27, and into the timer cam28, from whence it passes through the wire 29., The normal course ofsaid current being to pass into the variable resistance coil 30, acrossthe contact points into the plate 33, and thence back to the battery,vvia wire 34. However, when, the plate 31 becomes sufciently heated toexpand so as. to break the contact between the plates 31"and 33, the

course of the current through the iron wire coilwill be immediately cutolf and shunted into the high resistance winding 50, through the wire52.' As soon'as the current enters -said coil, itl tends to energize thecore of the electro-magnet, which in turn attracts the pivoted armature36, in such a manner that one end of said pivoted armature will bebrought into contact with the plate 31, so lo as to maintain the openingbetween the plates 31 and 33; this condition being maintained throughoutthe time that the main circuit is closedA by the inadvertent continuedclosure of the timer contacts.

From the above, it will' be seen that the iron wire, together with thecompound plate 31, will be entirely cut out of the main circuit, of thecurrent, as soon as the break between the contacts 31 and 33 occurs,thus permitting the iron wire to cool 0H and regain its normal conditionso that instantly upon the resumption of the normal operation of the cammember 2 8, relative to the timer contacts, the main circuit will beagain intermittently closed and opened in the 'usual manner. The tinewire winding which surrounds the core 47 of the magnet, is ofl such highresistance that the amount of current passing therethrough, is verysmall, being only sufficient to maintain .the core of dition to retainthe magnet in the attracted position, shown in Fig. 1.

From the above description, it will be obvious that as soon as the timercam 28 assumes its normal operation, the main cir.- 'cuit will be brokenand this will-stop the flow of current through the fine winding 50,because of the diiference in resistance between the main circuit and thewinding 50. A Now, as soon as the flow of current through this-windingis stopped, the core 47 of the` electromagnet will become denergized,which will, of course, release the armature 3G from its attractedlposition, and` through the action of the spring 41, the contact plate-31 will be forced back to its normal position, into engagement with thecontact plate 33.

In some instances it may be desirable, that the initial cutting-down ortapering ed of the current through the medium' of thc iron wireresistance be omitted from the apparatus and means employed, whereby thethermo-static contact plate 31 will, upon acquiring a certaintemperature tend to act use of some metals, as for instance copper,

the magnet in a suiiiciently energized con? as heretofore described, andautomatically.

in the make up of this coil, there will be no appreclable cutting downof the current, previous to the opening of the circuit,

through the action of the thermostatic plate a ous elements of theinvention, may be made without departing from the spirit and scope ofthe present invention, as set forth in the following claims.

What I claim is as follows:

l.` In a circuit controlling device, the combination with a source ofelectrical energy, and a main circuit connected therewith; of anautomatic circuit breaker located in said main circuit and including aresistance which increases its resistance with increases of itstemperature, said resistance operating upon said automatic circuitbreaker to break the circuit through said resistance, upon an abnormaliow of current therethrough; said circuit breaker having provisionswhereby the circuit through the resistance will be held open until thecurrent in the main circuit is broken, when said provisions operate toreestablish the circuit through the resistance. l

2. In a circuit controlling device, thecombination with a source ofelectrical energy, and a main circuit connected therewith; of

an automatic circuit breaker located in said main circuit and includingan iron wire resistance connected in the main circuit, said. circuitbrealwralso including a thermal device. operated b v the heating of theiron wire resistance to break the circuit through said resistance, uponan abnormal flow of current therethrough; said circuit breaker ha vingprovisions whereby the circuit through the. resistance will be held openuntil the. current in the main circuit is broken, l when said provisionsoperate to reestablish the circuit through the resistance.

3. In a circuit controlling device, the combination with a source ofelectrical energy; a. main circuit connected therewith; a make and breakdevice adapted to open and close llO the main circuit; of a memberhaving a posi tive coeiiicient of resistance connected with saidcircuit; a thermostatic circuit breaker controlled by said member tobreak the circuit through said member, upon an abnormal flow of currentltherethrough; andv means operable by current from the main circuit tomaintain open the circuit through and break device located in saidcircuit and adapted to close and open said circuit; an

automatic circuit breaker also located inl said circuit and includingprovislons operable to break said circuit when an abnormal iiow ofcurrent occurs therethrough, due to i the retention of the make andbreak device in circuit closing position; and means 'operable by thecircuit current to maintain said circuit breaker in open position, butto close said circuit breaker when said make and break device moves intoits position to break the circuit. Y

5. In a circuit controlling device, a thermo-electrical means normallyin series with an electrical circuit and adapted to break said circuit,of current therethrough; and electrically controlled meansoperable uponthe opening of this circuit by said thermal means, for maintaining saidcircuit in open condition throughout the abnormal flow of current.

6. In a circuit controlling device, a thermo-electric g device connectedwith a main electrical circuit, wherebysaid circuit will be broken, uponan abnormal ow of current through said thermo-electric device; a shuntcircuit including instrumentalities for maintaining theJnain circuitinfopen condition, until said circuit is broken at another point; andmeans for returning the instrumentalities to their normal position andto concurrently close the opening in the main circuit, which tion of thethermo-electric device, as soon as the normal operation of the system isestablished.`

7. In a circuit controlling device, a circuit breaker, comprising a pairof normally closed lcontact elements, one of said contact elementshaving a high coetlicient of expansion; a conductive element having apositive coeicient of resistence connected to .an electrical circuit; ofan electrically actuated mechanism, comprising an electricalconductorhaving a normal resistance greater than the normal resistance of theupon an abnormal flowis effected by the opera?V conductive element, andconnected to the f said circuit so that it is normally shunted by theconductive element, but is adapted to be placed in series with the saidcircuit when the normally closed contact plates have been initiallyopened.

In a circuit controlling thermo-electric circuit breaker comprising aconductive element having a positive coeilicient of resistance and acontact strip electrically connected with said conductive element andhaving -a high coeliicient of expansion, whereby when an abnormal flowof current passes through said element, having a positive coefficient ofresistance, the ,said element will increaseV its resistance to cut downthe flow of current therethrough, whereby when the resistance thereofreaches a determined point, the temperature of said element will be suchas to cause the eXpansion of the contact element having aL highcoeflicient of expansion and thus break the contact between said contactelements.

9. In a circuit controlling device, a thermo electric circuit breakercomprising an iron wire element and contact. elements including acontact strip electrically connected therewith, and a reinforcingelement associated with said contact strip, said strip having a highcoefficient of expansion, whereby when an abnormal How of current passesthrough said iron wire element, said element will initially increase itsresistance to cut down 'the flow of current therethrough, the increasedresistance thereof proportionately increasing the temperature thereofand thus causing an expansion of the contact strip so as to break thecontact between the contact elements; and electrically controlled meansadapted to be brought into operation device, a

by the actuation of the circuit breaker, for

maintaining the contact between said contact elements in open conditionuntil the iow of current has again returned to normal.- In testimonywhereof I affix my signature in the presence of two subscribingwitnesses.

JAMES H. KIEFER. Witnesses: v

THOMAS J. BYRNE,

BERT. R. SANDMAN.

